When we are connecting across the internet to LDAP servers, we should be using LDAPS if at all possible. I propose adding another variable to the LDAP config and changing C4::Auth_with_ldap to be able to do LDAP or LDAPS Net::LDAPS is functionally equivalent to Net::LDAP so will require minimal code changes.
This doesn't require code changes at all. If LDAP server is specified as <hostname>ldaps://ldap.example.com</hostname> Net::LDAP will use SSL connection to it. I'm using similar configuration for a while.
This bug is mentioned in: Bug 5406 Improve translation script http://lists.koha-community.org/pipermail/koha-patches/2010-December/013418.html
No code change necessary, marking invalid.